HW5-Chapter5 Chem106 - Balancing a Double Replacement Reaction

Now that we have put a coefficient of 3 in front of CaSO4 and a coefficient of 3 in front of CaCl2, what coefficient should go in front of AlCl3 to balance both the Cl atoms and the Al atoms? 3CaSO4+?AlCl3→3CaCl2+Al2(SO4)3

? = 2 There are now 6 chlorine atoms and 2 aluminum atoms on each side of the equation. The final balanced equation looks like this: 3CaSO4+2AlCl3→3CaCl2+Al2(SO4)3

Notice that "SO4" appears in two different places in this chemical equation. SO 2−4 is a polyatomic ion called sulfate . What number should be placed in front of CaSO4 to give the same total number of sulfate ions on each side of the equation? ?CaSO4+AlCl3→CaCl2+Al2(SO4)3

? = 3

Now that we have put a coefficient of 3 in front of CaSO4, what coefficient should go in front of CaCl2 to balance calcium (Ca)? 3CaSO4+AlCl3→?CaCl2+Al2(SO4)3 HINT: How many calcium atoms currently appear on the left side of this equation? 3CaSO4+AlCl3→CaCl2+Al2(SO4

? = 3 By placing a coefficient of 3 in front of calcium chloride, we have indicated 3 calcium atoms on the right to match the 3 calcium ions on the left: 3CaSO4+AlCl3→3CaCl2+Al2(SO4)3 HINT = 3